Molecular phylogeny and historical biogeography of Parnara butterflies (Lepidoptera: Hesperiidae)

Abstract

The butterfly genus Parnara (Hesperiinae: Baorini), of which some are major pests of economic crops (e.g., rice, wild rice stems and sugarcane), currently consists of 10 species and several subspecies and has a highly disjunct distribution in Australia, Africa, and Asia. We determined the systematic relationships and biogeographical history of the genus by reconstructing the phylogeny based on eight genes and 101 specimens representing all 10 recognized species. Four species delimitation methods (ABGD, bPTP, GMYC and BPP) were also employed to assess the taxonomic status of each species. Based on these results and analyses, we recognize 11 extant species in the genus. The status of the taxon P. naso poutieri (Boisduval, 1833) from Madagascar is revised as a distinct species, Parnara poutieri (Boisduval, 1833) stat. rev. The subspecies P. guttata mangala (Moore, 1866) syn. nov. is synonymized with P. guttata guttata (Bremer & Grey, 1853), while P. bada (Moore, 1878) is provisionally treated as a complex of two species, namely P. bada and P. apostata (Snellen, 1886). The monophyly of Parnara is strongly supported, with the following relationships: P. amalia + ((P. monasi + (P. poutieri + P. naso)) + ((P. kawazoei + P. bada complex) + (P. ganga + (P. ogasawarensis + (P. guttata + P. batta))))). Divergence time and ancestral range estimates indicate that the common ancestor of Parnara originated in an implausible area of Australia, Africa, and Oriental region in the mid-Oligocene and then differentiated in the late Miocene-late Pliocene. Dispersal and range expansion have played an important role in diversification of the genus in Asia and Afica. Relatively stable geotectonic plates at the time when most extant lineages appeared during the late Miocene-early Pliocene might have been the factor responsible for the relatively constant low dynamic rate of diversification within the group.